Proof in primaries for Senate fixtures

WASHINGTON – Voters in four states will go to the polls Tuesday in primary elections that could offer the best window so far into the level of anti-incumbent, anti-establishment sentiment in the electorate.

Arkansas, Kentucky, Oregon and Pennsylvania hold primaries Tuesday, and political observers are paying close attention to all but Oregon, where incumbent Democratic Sen. Ron Wyden is expected to win handily.

Democrats and Republicans are sweating over Senate contests in Arkansas, Kentucky and Pennsylvania, which are considered prime tests of voter discontent with incumbents and the power of the tea party movement.

“The overall environment has changed where you have an element of voters in both parties who are unhappy with the direction (their) party is headed,” said Jennifer Duffy, a senior editor of the Cook Political Report. “You have progressives who are unhappy with the Democrats, and on the Republican side you have the conservative element, the tea party, which believes this president and this Congress (are) out to change the fabric of American life.”

In Pennsylvania, incumbent Democratic Sen. Arlen Specter, who left the Republican Party last year because he thought he’d lose a GOP primary, has watched his comfortable double-digit lead evaporate to a statistical dead heat over lesser-known Rep. Joe Sestak.

Specter’s slide has occurred despite the strong backing of President Barack Obama, the AFL-CIO and Pennsylvania’s popular Democratic governor, Ed Rendell.

In Kentucky, endorsements from GOP kingmakers such as Senate Minority Leader Mitch McConnell, R-Ky., and former Vice President Dick Cheney apparently aren’t working for Trey Grayson in his quest for the Senate seat held by Republican Jim Bunning, who’s retiring.

Grayson, Kentucky’s secretary of state, trails tea party-backed Rand Paul by double digits. Paul’s a political newcomer and the son of Rep. Ron Paul, R-Texas, a 2008 presidential candidate.

The Kentucky race is seen as a major test of the tea party’s clout as a grass-roots movement powered by disgruntled conservatives who bemoan what they see as an unprecedented expansion of federal government.

While there’s Republican hand-wringing in Kentucky, national Democrats are breathing a little more easily over Arkansas, where two-term Democratic Sen. Blanche Lincoln is battling Lt. Gov. Bill Halter, who’s challenging the centrist incumbent from the left.

Halter’s campaign has received millions of dollars from liberal Democrats and strong support from labor unions, which are angry over Lincoln’s opposition to a government-run component in the health care legislation and to a so-called “card check” measure that would make it easier for unions to organize workers.

Despite such opposition, Lincoln led a Mason-Dixon survey earlier this month by 8 percentage points.