What is one reason that V. O. Key identified as a barrier to strong political parties in Texas?

due to Lack of interest in politics

Explanation:

As Texas Democrats allocate presidential nominating delegates both by election and caucus

but modern source of influence has weakened political parties in Texas is national politics

and as as consequence of weak political party in Texas Political outsider often gain statewide office

and due to

lack interest in politics V. O is main barrier to strong political parties in Texas