In Arkansas, centrist Democratic Senator Blanche Lincoln failed to win a majority of votes in the primary against a left-leaning challenger, and is headed to a June run-off for her party's nomination.

David Hawkings is managing editor of Congressional Quarterly Weekly, one of the leading print and online news media covering Congress. Hawkings agrees that there is an unmistakable and prevailing anti-incumbent mood in the country.

"It is going to be a big anti-incumbent year, and a big anti-Washington year, and what is still left a little bit up in the air after last night is how much that anti-incumbent wave, how disproportionately that anti-incumbent wave, will wash over the Democrats," said Hawkings. "Or whether it is really even a wave."

Hawkings says Democrats say there is no upcoming Republican "wave" which will sweep scores of them from office, pointing to a special election for the U.S. House seat for the late Congressman John Murtha of Pennsylvania. Long-time Murtha aide and Democrat Mark Critz won that seat Tuesday in a conservative district that voted for Republican John McCain over Democrat Barack Obama in the 2008 presidential election.

There was another anti-incumbent slap in the face for establishment Republicans in Kentucky. Rand Paul, a grassroots conservative activist candidate, running under the "Tea Party" banner, scored a blowout win over the hand-picked Republican establishment candidate, Secretary of State Trey Grayson. Rand Paul, the son of libertarian presidential candidate Ron Paul, issues this warning in his victory speech.