Incumbents, Obama included, are at risk no matter their party at a time when the economically struggling public is sour on anyone linked to Washington. So, it seems, are lawmakers with a history of working with members of the opposite party.
Just ask Lugar.
Mourdock hounded the veteran senator over questions about his Virginia home — and Indiana residency — and his longtime Washington ties. The challenger also took Lugar to task over his collaboration with Obama. The two worked together on nonproliferation issues, and Lugar was one of only a handful of Republicans to vote to confirm Obama's two appointments to the Supreme Court.
It wasn't just those issues that didn't sit well with voters, who craved change after nearly four decades of Lugar representing them. That was clear from signs stating simply "retire Lugar" that dotted the roadside along U.S. 30 east of Valparaiso, a Republican-leaning town in northern Indiana.
"He's a good and decent man," Valparaiso Republican Bruce Garrison said of Lugar after casting his vote for Mourdock. "But how can the country keep going on the path it's on? And how can we send the same people back to fix it?"
It's that reject-the-status-quo strain among voters that incumbents up and down the ballot will find themselves having to fight against over the next six months.
That Lugar — an establishment candidate if there ever was one — fell to a tea party-backed Republican made clear that the divisions within the GOP that were on display in 2010 primaries across the country had not yet healed.
"There is an element of the Republican base, and it's stronger than ever now, that was never going to vote for Richard Lugar," said Dan Dumezich, a Lugar supporter from northwest Indiana and Romney's state co-chairman.
The split presents a huge challenge for Romney as he seeks to unify the Republican Party in the coming months.
He has campaigned as the establishment choice, but was beaten badly at times by insurgent favorites, first by former House Speaker Newt Gingrich in South Carolina and later in a series of contests by conservative former Sen. Rick Santorum.
Now Romney is working to mend the rifts. Whether he can — and whether the tea party and other conservatives rally behind him — won't be clear until November.
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