For those questioning money being the only factor in possibly losing Brohm:
Butch Jones at Tennessee made $4.11 million per year placing him 9th in the SEC but puts him in the 'range' of Malzahn @ Auburn ($4.73) who is #3. Jim McElwain @ Florida made roughly the same amount of $4.27 million.
Brohm's current contract is roughly $3.3 million per year which places him and would rank him 7th in the B1G with the capacity to earn more if results show. That would place him #28 in the country according to last year's
NCAAF Coaches Salary Graph by USA Today. I believe Purdue could easily match or exceed offers floated toward Brohm with the exception of the following programs:
SEC: Alabama & Texas A&M
B1G: OSU, Michigan, PSU
Big 12: Oklahoma & Texas
Pac 12: Oregon
ACC: FSU & Clemson
After the first 11 coaches in the USA Today poll from last year, the salary begins at $4.47 million for Clemson's Dabo Sweeney. I highly doubt that unless Brohm consistent has Purdue competing and/or winning conference titles, one of those programs will come sniffing around and be able to offer more than what Purdue could. At that point, I would imagine the AD would be able to match any offer or exceed it to make Brohm's decision to stay with what he has built at Purdue an incredibly hard one.
My point in a nutshell: If Purdue can and is willing to pay $3.3 million after the roughest patch of history...they'd be willing AND able to pay Brohm an additional $1-$2 million per year to ensure him staying. I have much more of a feeling it would have to do with other intangibles for Brohm such as increased support staff pay, increased salaries for assistant coaches, and new facilities/etc.