Mitt Romney's aides say his ongoing search for a running mate remains focused on prospects with "I could be President" qualifications ... That keeps the smart money on Ohio Senator Rob Portman, whose travels around the country on Romney's behalf are serving as something of a regional theater tryout ... There is also chatter about former Minnesota governor Tim Pawlenty, who might swing a state with 10 electoral votes but who spent a small fortune to supply his background materials to the McCain campaign in 2008 only to be passed over for a last-minute pick ... While the presidential contest dominates media coverage, moneyed interests are queuing up to influence control of the House and Senate ... As of now, Republicans look like a very solid bet to retain the House ... The Senate could go either way, with Republicans still to select nominees in Connecticut, Florida and Missouri ... Despite a throw-the-bums-out zeitgeist, a wave election seems unlikely because of crosscurrents on the economy, social issues and voter concerns about unified party control ... The occasional outlier poll notwithstanding, the Obama-Romney matchup remains tighter than jeans just out of the dryer ... Obama's best options to stage a midsummer surge all come with risks: more extensive time on the road campaigning could be perilous for a man with a highly visible day job; a joint Obama-Biden tour could turn into a double waste of resources; a roster of all-star convention speakers in Charlotte to outshine the Republicans in Tampa might lead to an off-the-leash Bill Clinton address ... One possible maneuver: an ad barrage drilling Romney for policy flip-flops to cement the case that the GOP nominee has no core beliefs.