At this time four years ago, Barack Obama’s campaign had about 30 field offices up and running in Iowa, compared to six offices for Republican presidential candidate John McCain.

Obama’s campaign has had eight Iowa field offices open this summer and is rolling out another 26 offices around Iowa this weekend. So far, Mitt Romney’s campaign has ten Iowa field offices, in addition to the unified Republican headquarters in Urbandale.

After the jump, I compare the field office locations for each presidential campaign, grouped by Iowa Congressional district. Where relevant, I’ve also noted competitive Iowa House and Senate districts near the Obama and Romney field offices, although I doubt either presidential campaign will do much for down-ticket Democratic or Republican candidates.

Polls closed across Iowa at 9 pm, and I will update this post periodically as results come in from around the states. Any comments related to today’s elections are welcome in this thread.

P.S.- As expected, Wisconsin Democrats fell short in their effort to recall Republican Governor Scott Walker.

UPDATE: Results are after the jump.  

The redistricting process and several Republican retirements have created many pickup opportunities for Iowa House Democrats. The devastating 2010 election left them nowhere to go but up in the lower chamber, where Republicans currently enjoy a 60 to 40 majority. Relatively few sitting House Democrats represent vulnerable districts.

Speaking to activists at the Polk County Democratic convention on March 10, I heard lots of optimism about the House races. After the jump I’ve posted some early thoughts on the seats up for grabs.

NOTE: A third Democrat, Nick Volk, filed nominating papers in this district on March 15.

Shelley Parbs announced today that she will run for Iowa Senate district 38. She is the second declared Democratic candidate in this district; the winner of the June primary will face first-term Republican Tim Kapucian, a Senate minority leader and ranking member of the Transportation Committee. Background on Parbs is after the jump, along with election-related developments in the two Iowa House seats that make up Senate district 38.

NOTE: On March 12, Democrat Shelley Parbs announced her candidacy in this district, and a third Democrat, Nick Volk, filed nominating papers on March 15.

Iowa Senate Democrats finally announced their challenger to first-term Republican Tim Kapucian last week, setting up a potentially competitive race in the new Iowa Senate district 38.

Republican business owner David Maxwell is running to represent the new Iowa House district 76. Previously declared GOP candidate Mark Dix dropped out of the race yesterday. A map of this swing district and background on Maxwell are after the jump.

UPDATE: Dix quit the race in November 2011, shortly after Republican David Maxwell declared his candidacy in House district 76.

Iowa’s new map of political boundaries created several competitive state House and Senate districts lacking an incumbent. Democrat Rachel Bly and Republican Mark Dix recently announced their candidacies in Iowa House district 76, covering Poweshiek County and most of Iowa County.