And the Democratic convention keynote speaker is ... Mark Warner

Barack Obama on Wednesday chose Mark Warner, Virginia's Senate candidate and former governor, to deliver the keynote address at the Democratic convention, underscoring Democrats' all-out effort to win the Southern state for the first time since 1964.

It also raises questions about the prospects of Obama choosing Virginia Gov. Tim Kaine as his running mate.

Warner is to speak on Aug. 26, the second day of the convention in Denver, while the yet-to-be-named vice presidential nominee is to address delegates a day later on Aug. 27. Sen. Hillary Rodham Clinton is also set to speak Aug. 26, an indication that Obama probably won't ask her to join the ticket.

Would Obama devote two major prime-time national addresses to politicians from the same state? It's possible, given the attention, money and manpower that Obama is lavishing on the state. Democrats consider the state the most promising as they seek victory in Southern and Western states that Republicans have held for decades.

Kaine has appeal, weaknesses

Kaine is seen by many voters as a new kind of Democrat, a man of faith who could talk about religion without it seeming like a prop. The Obama campaign sees him as a like-minded breath of fresh air who has shown he can win in a red state. But his similarities to Obama are also a potential weakness: He has a legislative record that is relatively thin and has virtually no experience in foreign policy.

While running mates typically complement the presidential candidate, Kaine, 50, more replicates Obama. He is an inspiring speaker, a Harvard-trained lawyer who spurned corporate work for civil rights. He eludes labels -- a Roman Catholic, he opposes the death penalty and abortion, yet has allowed several executions during his tenure and says he does not think abortion should be criminalized. He describes himself as pragmatic and a bridge builder. He has relatives who even hail from the same Kansas town as Obama's do.

"He reinforces a basic message Barack Obama wants to send about a new, non-Washington era," said Robert Holsworth, the director of the Center for Public Policy at Virginia Commonwealth University. But "he's going to have trouble demonstrating political accomplishments."

A boost for Warner

For Warner, a place in the national spotlight will at the very least boost his Senate campaign; he is trying to succeed retiring Republican John Warner.

Obama's campaign called Warner an innovative businessman -- he became wealthy from work and investments in the cellular telephone industry -- fitting for the evening's theme of economic opportunity.

Also speaking that night will be six governors -- Janet Napolitano of Arizona, Kathleen Sebelius of Kansas, Ted Strickland of Ohio, Ed Rendell of Pennsylvania, Deval Patrick of Massachusetts and Brian Schweitzer of Montana -- along with Sen. Bob Casey, Jr. of Pennsylvania and former Denver Mayor Federico Pena.