GOP establishment candidates notch wins in key primaries

Republican establishment favorites dominated virtually across the board in the season’s biggest primary day so far, with Senate GOP Leader Mitch McConnell fending off a challenge from his right in Kentucky and Tea Party-aligned candidates falling short in several other states.

McConnell was able to easily best Tea Party-backed challenger Matt Bevin, a businessman who entered the race with high hopes of knocking off the Senate’s most powerful Republican. Bevin, though, struggled through a string of controversies and under a withering barrage of McConnell ads — the GOP leader won by a roughly 2-to-1 margin. His tougher contest will come in the fall, when he faces Democrat Alison Lundergan Grimes.

Several of the primary contests across six states on Tuesday are considered critical to Republicans’ hopes of picking up the six Senate seats necessary to take the majority in the upper chamber. In Kentucky and Georgia, Republicans are defending seats they can ill afford to lose.

Establishment-backed candidates have generally fared better than their Tea Party rivals this year, with the exception being Ben Sasse’s victory last week in a Nebraska Senate primary. But even among those with party heavyweight backing, the debate is familiar — with candidates battling for the conservative mantle.

Republicans are looking to Dr. Monica Wehby, a pediatric neurosurgeon and political newcomer in Oregon, to pull off an against-the-odds victory in territory where a Republican has not won a statewide election since 2002. However, some believe that first-term incumbent Merkley is vulnerable because he has enthusiastically supported ObamaCare.

In another defeat for the grassroots conservative movement, attorney Bryan Smith also failed to beat Idaho GOP Rep. Mike Simpson Tuesday night. Smith had the backing of the conservative anti-tax Club for Growth, but Simpson won by a double-digit margin.

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