Democratic Sen. Bayh won't seek re-election

Senator Evan Bayh (D-IN) speaks at the 2008 Democratic National Convention in Denver, Colorado, August 27, 2008.

WASHINGTON (Reuters) - U.S. Senator Evan Bayh, a popular Democrat seen as having a good shot at a third term, said Monday he won't run again because of the kind of bitter politicking that has put President Barack Obama's whole agenda in jeopardy.

Bayh of Indiana said that "narrow ideology" was ruling lawmakers' decisions, thwarting useful work at a time when a bipartisan approach was urgently needed, and sapping his desire to remain in Congress.

Bayh's surprise decision underscored the Obama's and Democrats' problems in the often gridlocked Congress as well as the party's difficulty heading into November's election.

Even with Democrats in firm control of both chambers, Obama's first year in the White House was marked by struggle to win his domestic priorities. He enters his second year trying to salvage his healthcare and energy initiatives before they sink into an election-year stall, while also battling for a multibillion-dollar jobs bill and financial regulatory overhaul.

"I love helping our citizens make the most of their lives, but I do not love Congress," Bayh said at a news conference in Indianapolis, making little effort to hide his frustration at the slow pace in the Senate.

He is the fourth sitting Democratic senator not to run in November -- leaving seats up for grabs in Indiana, Illinois, North Dakota and Connecticut -- and analysts say six more Democratic seats are vulnerable to a strong Republican challenge in November.

Democrats now hold control of the Senate, 59-41, and the House, 255-178, with two vacancies, but all House seats are up for election as well as 36 of the 100-seat Senate.

Republicans are expected to reduce Democrats' big majorities in Senate as well as the House of Representatives, especially if an anti-incumbent drive develops as seems to be happening.

Republicans scored a shock upset victory in a special Senate election in Massachusetts last month which cost them the crucial 60th vote needed to hold Republican stalling tactics at bay. Democrats' concern for their political future will be heightened by Bayh's decision.

'GAME CHANGER'

A spokesman for the Indiana Republican Party called Bayh's decision "a game changer," and said several Republicans including former Senator Dan Coats and former Representative John Hostettler are expected to run. "We're confident in our chances this fall," Trevor Foughty said.

After Bayh's announcement, the nonpartisan Cook Political Report changed the Indiana race to "Lean Republican," from "Lean Democrat."

Democratic Senate Campaign Committee head Senator Robert Menendez wasted no time attacking the Republican challengers.

"We will have a strong Democratic candidate on the ballot there, who will be running against a weakened Republican field, including federal lobbyist Dan Coats whose baggage is now hardly a secret," he said in a statement.

Democrats have criticized former Senator Coats over his residency in Virginia for the past decade, implying that would make him a questionable candidate to represent Indiana voters.

With Bayh out of the race, the likely candidates for the Democratic nomination for the Senate include a pair of House members, Representatives Brad Ellsworth and Baron Hill, a senior party aide said.

Bayh, 54, was elected to the Senate in 1998 and 2004 and insisted he was confident he could win a third six-year Senate term if he had wanted one. Published reports said Bayh had millions of dollars available for a re-election run.

The son of former U.S. Sen. Birch Bayh, he has been a centrist who sought common ground with Republicans. He said his decision should not reflect adversely on his fellow senators or on the president.

"I look forward to working with him during the next eleven months to get our deficit under control, get the economy moving again, regulate Wall Street to avoid future financial crises and reform education," Bayh said.

In a statement Obama praised his bipartisanship and thanked him for his service.

Bayh was not only a popular senator but also a former governor of Indiana. He had once been seen as a possible presidential contender and was regularly cited as a potential pick for vice-president.

But he was clearly frustrated at the strong partisan streak in the Senate where most major votes are along party lines.

"Two weeks ago, the Senate voted down a bipartisan commission to deal with one of the greatest threats facing our nation: our exploding deficits and debt," Bayh said. "Just last week, a major piece of legislation to create jobs -- the public's top priority -- fell apart amid complaints from both the left and right."

(Additional reporting by Steve Holland and Thomas Ferraro, James Kelleher in Chicago, Karen Schefmeyer in Indianapolis; Editing by Jackie Frank)