Former Pennsylvania Senator Rick Santorum is officially in as a candidate for the Republican nomination for President, as of today. Santorum, while an outspoken social conservative, is considered likely to struggle to appeal to all three constituencies of the Republican party — fiscal conservatives, social conservatives and foreign policy hawks. It's not so much that Santorum lacks expertise or leadership on the other issues, he did rise to the number three position in the Senate, but that he has spent most of his political capital on defining himself through social issues. 

In the past, Santorum has been able to defeat numerous Democratic incumbents in the swing state of Pennsylvania, proving he is able to appeal to a wider electorate. If he is able to speak to such a wide audience as effectively as he has in the past, he'll do a lot better than many talking heads are predicting. 

With a crowded field, Santorum has been trying to stick out lately, including by going after other conservative candidates. This could be more dangerous to his stock than other candidates he goes after. Social conservatives in recent years have shown an interest in backing candidates who are, to paraphrase Mike Huckabee, "conservative but not angry about it." If he is able to do that in a positive way, like Huckabee did in Iowa in 2008, he'll be much more successful. 

Santorum has been able to sign up a few well known and respected operatives in the early states, and he is certainly counting his lucky stars that Mike Huckabee opted out of the race, leaving social conservatives to re-look at the field for their candidate. A big first measuring stick to analyze Santorum's viability will be his fundraising numbers that are due in mid-July. If Santorum is able to convince some big donors that his candidacy is worth backing, it will cause the chattering classes to give him more coverage and grassroots activists to give him a longer look. 

While it hasn't been written about much, we think Santorum will face an uphill climb against Tim Pawlenty for the social conservative wing of the party. Pawlenty is currently the only evangelical Christian in the race and his home church pastor is the President of the National Association of Evangelicals. Much like Huckabee, Pawlenty puts a sunny disposition on social conservative issues and is able to speak about them in ways that middle-class, mid-west voters appreciate.

Look to the first real debate, only a week away at this point, for Santorum to rise above the pack with a few well laid punches against Mitt Romney, Tim Pawlenty, or other first tier candidates. His ability to hit other conservative candidates without angering voters for breaking Reagan's 11th commandment to not attack other Republicans will be an early indication of the viability of his candidacy.

According to leading social conservative activist Ralph Reed, social conservatives are more focused on economic issues this cycle, but they still expect a candidate "that can walk and chew gum at the same time." Unfortunately for Santorum, he is more known for his chewing gum on social issues, than his ability to walk on economic or foreign policy issues.