As Organizing for Action embarks on a month of intense grass-roots activity, it hopes to show that its network of volunteers can influence and, more importantly, actually persuade lawmakers on pivotal issues such as gun control, the environment and immigration reform.

The group’s leaders insist that its backers are already shaping the legislative debate. At a day-long summit meeting Monday of top volunteers and staff in Washington, national organizing director Sara El-Amine proclaimed: “The transition of your smart, battle-tested tactics to members of Congress has worked.”

El-Amine  pointed to Republican Sen. Mark Kirk of Illinois as an example of OFA's powers of persuasion. She said Kirk dropped his opposition to a comprehensive immigration reform measure last month after OFA volunteers in his state handed out bilingual fliers and held 12 public events highlighting his stance.

“You made sure that the press and members of Mark Kirk’s constituency heard where he stood,” she said. “And just three days after your big slew and drumbeat of events … Senator Kirk came out in support of immigration reform.”

But is OFA why Kirk decided to speak out in favor of comprehensive immigration reform?

Kirk spokeswoman Nicole Barrett declined to say whether OFA’s efforts, which began on June 19, had any impact on his decision. What did clearly influence him was a last-minute deal in the Senate to add a $38 billion border security “surge” to the immigration bill.

The amendment was introduced by Republicans John Hoeven of North Dakota and Bob Corker of Tennessee on June 20. On June 24, Kirk issued a statement praising the enhanced border security provisions in the immigration reform bill, which he said he would back.

Though Barrett declined to specify what influenced Kirk's switch in support, a press release from his office stated that Kirk "hailed the inclusion of key provisions" which included the doubling of the size of border control.

"The decision is should the border security amendment pass, I will be able to support the final legislation because then I will be able to assure the people of Illinois that the border is well covered with 21,000 border agents added, one every thousand feed, I think we got the border covered," Kirk told the Chicago Sun-Times the day the amendment was introduced.

And, then there is the fact that Kirk is a freshman Republican representing a heavily Democratic state. When he runs for a second term in 2016, he needs a few specific examples of working across the aisle to make the case that he is problem solver not a partisan.

That last point, to our mind, is by far the biggest deciding factor in Kirk's decision to support the Senate immigration bill. Is it possible that representing a Democratic state made OFA's case that much stronger? Absolutely, in that it reminded him (although he probably didn't need reminding) that he needs to win over a large number of Democrats to have a chance at a second term.

Victory, especially in politics, has a thousand fathers. OFA is one of them when it comes to Kirk's vote for immigration reform.

This post was updated on 7/24/13 at 12:52 p.m.