Michael Castle is a member of an endangered species in the U.S. Congress: He's a moderate Republican. He's also a key figure in next year's election.Castle is running to fill the Senate seat for Delaware formerly held by U.S. Vice President Joe Biden, and his likely Democratic foe is Biden's son, Delaware Attorney General Beau Biden.
Castle, a member of the House of Representatives since 1993, is seen as among the Republicans' best bets to end the Democrats' 60-vote super-majority in the 100-member Senate.
Sixty votes lets Democrats pass legislation without Republican support in that chamber, including a landmark overhaul of the U.S. healthcare system.
"Castle's Senate race promises to be one of the most watched next year," said Jennifer Duffy of the nonpartisan Cook Political Report. "The stakes are high on a number of levels."
The contest unfolds as conservative activists take on Republican moderates like Castle, fueling an internal ideological battle that has pushed the party farther to the right and made it tougher to find common ground with Democrats in Congress.
But these conservatives aren't expected to tangle much, if at all, with Castle in the November 2010 election.
That's because the popular nine-term lawmaker -- who as tiny Delaware's only U.S. representative is elected statewide -- and former two-term governor is seen as the only Republican able to beat Biden in the predominately Democratic state.
CONSERVATIVES 'YIELD TO THE WORLD AS IT IS'
"Folks on the right, and frankly I'm one of them in terms of voting record, have to yield to the world as it is and not necessarily how they wish it would be," said Senator John Cornyn, who as chairman of the Senate Republican campaign committee recruited Castle to run.
"The world as it is in Delaware is that if Mike Castle didn't run, Beau Biden would be the next senator from Delaware," said Cornyn.
Still, Castle said he expects to draw "some heat" from
conservative activists, like he did at town-hall meetings this year.
At one meeting, he was called a "traitor" for being one of eight House Republicans to back a Democratic bill to fight climate change.
At an another, he was booed for defending President Barack Obama against a conspiracy theory pushed by fringe groups that the Democratic president is not a U.S. citizen.
"There have been times that they have been less than happy with me," said Castle. "And they don't forget."
Castle said Republicans need to be less strident and more tolerant of different points of view if they expect to win back control of Congress and the White House.
"You can't be a majority party unless you are accommodating of that," Castle said. "Democrats have done a better job at that than we have."