rank                           constituency winning party 2007  swing to gain labour 's place 2007             result
0     1  carmarthen west & south pembrokeshire       conservative           0.17                  2nd  conservative hold
1     2                             clwyd west       conservative           3.05                  2nd  conservative hold
2     3                  preseli pembrokeshire       conservative           5.58                  2nd  conservative hold
3     4                               llanelli        plaid cymru           7.04                  2nd        labour gain
4     5                          cardiff north       conservative           7.19                  2nd        labour gain

Table as JSON:
{"rank":{"0":1,"1":2,"2":3,"3":4,"4":5},"constituency":{"0":"carmarthen west & south pembrokeshire","1":"clwyd west","2":"preseli pembrokeshire","3":"llanelli","4":"cardiff north"},"winning party 2007":{"0":"conservative","1":"conservative","2":"conservative","3":"plaid cymru","4":"conservative"},"swing to gain":{"0":0.17,"1":3.05,"2":5.58,"3":7.04,"4":7.19},"labour 's place 2007":{"0":"2nd","1":"2nd","2":"2nd","3":"2nd","4":"2nd"},"result":{"0":"conservative hold","1":"conservative hold","2":"conservative hold","3":"labour gain","4":"labour gain"}}