Older voters, along with voters from urban areas and voters from areas that supported President Obama in the last election are taking advantage of Minnesota's expanded absentee voting option at higher rates than other groups, leading the charge toward record voter participation statewide.

A Star Tribune analysis of early voting data shows that retirement-age voters are casting their ballots early at a disproportionately high rate, putting the average age of early voters at 63, compared to the average age of registered voters, which is 51. Meanwhile, voters from Hennepin and Ramsey counties are opting for absentee ballots at the highest rate of any area, while people in outer-ring suburbs are the least likely to vote early.

Because Minnesota does not require voters to identify party affiliation, the data from the nearly 200,000 ballots collected by elections officials through Oct. 24 does not reveal whether Democratic nominee Hillary Clinton or Republican nominee Donald Trump is picking up more support among early voters. But it does provide a glimpse into the voting patterns of districts that went either red or blue in the last election — and a clearer picture of the Minnesotans who are among the 21 million people across the country who have already cast their votes.

With one week to go until Election Day, nearly a quarter of voters in a handful of presidential battleground states, including Florida and Nevada, have already voted as the campaigns are working to bank large numbers of votes before Election Day.

In Minnesota, the latest statistics released by state elections officials on Oct. 27 show that 250,123 voters had submitted their ballots. That's still a relatively small piece of the state's total voter base; as of June, there were about 3.2 million registered voters.

But Minnesota Secretary of State Steve Simon said past voting trends indicate that a flood of early ballot returns is likely in the days leading up to the election, and that the early numbers indicate that voters have embraced the "no-excuses" absentee voting system that was first introduced here in 2014. He said the ease of requesting a ballot by mail or turning up to one of the early voting centers "knocks down a barrier" to voting. "People have now come to understand that they can vote from home, vote from their kitchen table, and they like having that option on the menu," he said.

Some voters are more enthusiastic about the new options than others. The analysis used absentee voting data from the Secretary of State — which showed voters' names, address, precinct and the date their ballot was accepted, but not their party or for whom they voted — and voter registration and voter history data to study demographic patterns.

See more charts on Minnesota's absentee voters

It showed that the largest percentage of early ballots submitted came from people over the age of 65. Voters in the 65-to-74 age category accounted for 27 percent of absentee ballots, though they only make up 13 percent of the state's registered voters. Voters 75 and older submitted 23 percent of the absentee total, but account for just 10 percent of registered voters.

Younger voters, however, were less active. The age groups between 25 and 44 collectively account for nearly one-third of the states registered voters — but only a combined 12 percent of the absentee ballots submitted. The youngest voters, between 18 and 24, account for just 5 percent of absentee ballots received.

There are also geographic gaps; 39 percent of the ballots submitted were from Hennepin and Ramsey counties, generally a Democratic stronghold that accounted for 33 percent of total votes cast in 2012. Participation rates from voters in suburban areas closest to Minneapolis and St. Paul, along with those in outstate communities and smaller cities like Duluth and Rochester, match closely with those from the last presidential election. One area, however, differs: outer-ring suburbs, which account for just 7 percent of absentee ballots, but 10 percent of the electorate in 2012.

See more charts on Minnesota's absentee voters

Meanwhile, nearly 57 percent of absentee votes were cast in precincts that voted for Obama in 2012, with 43 percent coming from precincts that voted for Republican Mitt Romney. That trend is a close match with the divide in 2012, where 55 percent of voters lived in Democrat-leaning precincts, and 45 percent came from places that backed Republicans. (Obama took 53 percent of the vote to Romney's 45 percent.)

Both parties are running their own calculations, based on public election data and their own voter databases, linking voters with parties through their participation in party primaries, among other factors.

DFL Chairman Ken Martin said his party estimates that 65 percent of the votes cast so far are from Democrats. He said the party has been able to be more effective in its outreach by sorting out who has and hasn't voted and target those still potentially making up their minds. "We're not wasting time on people who have already voted," he said.

Minnesota Republican Party Chairman Keith Downey disputes Martin's estimate. He said Republicans have historically picked up momentum in the final stages of absentee voting and are turning out in force outside of Minneapolis and St. Paul. "Our effort has been very focused on our battleground congressional and legislative districts, and we feel very good there," he said.

The absentee votes won't be tabulated until Election Day, but elections officials will begin opening them at the close of the business day on Tuesday. That's also the deadline for a little-known provision in the state's election laws, which allows early voters to cancel their initial ballot and request a new one.

Up until 5 p.m. Tuesday, voters can contact the early voting location where they voted, or the location to which they mailed their ballot and ask that their ballot be destroyed. They can opt instead to vote on Election Day, or to request a new absentee ballot. Simon cautioned that absentee ballots must be received by Election Day, so people mailing in their ballots don't have much time to wait.

Erin Golden • 612-673-4790